What Is E15 And E85

Are you curious about ethanol blends and how they work? If so, you’re in the right place. Ethanol, a renewable fuel derived from plant material, has been blended with gasoline for decades to create fuel blends with varying levels of ethanol content. Two of the most commonly used blends are E15 and E85.

In this article, we’ll explore the differences between these blends and how they can impact your vehicle’s performance and fuel economy. Before we dive into the specifics of E15 and E85, it’s important to understand the basics of ethanol as a renewable fuel.

Ethanol is made from plant materials such as corn, sugar cane, and switchgrass. It can be blended with gasoline to create a more environmentally friendly fuel option. Ethanol is considered renewable because it is made from plants that can be grown and harvested repeatedly, unlike fossil fuels which are finite resources.

As consumers become increasingly aware of the impact of their choices on the environment, renewable fuels like ethanol are becoming more popular.

Understanding Ethanol as a Renewable Fuel

You may not know this, but ethanol is a renewable fuel that can be produced from crops like corn and sugarcane, and it’s commonly used in blends like E15 and E85.

The production process involves fermenting the starch or sugars in the crops to create ethanol. This process is known as bioconversion, and it’s been used for centuries to create alcohol for consumption.

However, the use of ethanol as a fuel has grown exponentially in recent years due to its renewable nature and potential to reduce greenhouse gas emissions.

The environmental impact of ethanol production is a controversial topic. While ethanol is considered a renewable fuel, its production requires a large amount of energy and resources. Additionally, the use of crops for fuel production can lead to increased food prices and competition for land.

However, proponents of ethanol argue that its use can reduce dependence on fossil fuels and lower overall carbon emissions. As with any fuel source, it’s important to weigh the benefits and drawbacks before making a decision on its use.

E15: The 15% Ethanol Blend

Let’s talk about E15, the 15% ethanol blend that’s becoming more and more popular at gas stations across the country.

Ethanol production has been on the rise in recent years, and E15 is just one example of how we’re using this renewable fuel to power our vehicles.

E15 contains 15% ethanol and 85% gasoline, making it a higher ethanol blend than E10, which contains 10% ethanol and 90% gasoline.

While E15 has been praised for its potential to reduce our reliance on fossil fuels, it’s important to consider its environmental impact.

Ethanol production requires a significant amount of land, water, and energy, and can contribute to deforestation, soil erosion, and water pollution.

Additionally, some studies have suggested that ethanol production may not actually reduce greenhouse gas emissions as much as we originally thought.

It’s important to weigh the pros and cons of E15 and other ethanol blends, and to continue researching ways to make ethanol production more sustainable.

E85: The 85% Ethanol Blend

E85, an 85% ethanol blend, is a renewable fuel option that can be used in Flex Fuel Vehicles (FFVs). These vehicles are designed to run on gasoline or any blend of ethanol up to 85%.

E85 is becoming increasingly popular among drivers who want to reduce their environmental impact. The use of E85 can reduce greenhouse gas emissions by up to 29% compared to gasoline. It also has a higher octane rating than gasoline, which can improve engine performance.

However, it’s important to note that FFVs typically have lower fuel economy when using E85 compared to gasoline. Overall, E85 is a viable option for those looking to reduce their carbon footprint, but it’s important to consider factors such as vehicle compatibility and fuel efficiency before switching from traditional gasoline.

Differences Between E15 and E85

When it comes to choosing between E15 and E85, there are several differences to consider.

One of the main differences is ethanol content, as E15 contains 15% ethanol while E85 contains 85% ethanol.

Another important factor is vehicle compatibility, as not all vehicles are designed to run on E85.

Finally, there is a difference in performance and efficiency, as E85 can provide more power but may result in lower fuel economy compared to E15.

Ethanol Content

The high ethanol content in E15 and E85 fuels is one of the key differences between the two. Both fuels contain much higher levels of ethanol than traditional gasoline, which is made primarily from fossil fuels.

Ethanol is a renewable fuel that’s produced from plants, making it a more sustainable and environmentally friendly option for powering our vehicles. Ethanol production has a much lower environmental impact than traditional fossil fuel production as it produces significantly fewer greenhouse gas emissions.

Additionally, because ethanol is made from plants, it’s a renewable source of energy that can be replenished over time. By choosing fuels with high ethanol content, you can significantly reduce your dependence on fossil fuels and help create a more sustainable future for our planet.

Vehicle Compatibility

Switching to high ethanol fuels like E15 and E85 can be a great way to reduce our carbon footprint. However, it’s important to understand that not all vehicles are compatible with these fuels. Before making the switch, it’s crucial to check your vehicle’s owner manual to see if it’s approved to use E15 or E85.

One factor to consider is fuel efficiency. Most vehicles will see a decrease in fuel efficiency when using high ethanol blends. This is because ethanol has a lower energy density than gasoline, meaning it takes more ethanol to produce the same amount of energy as gasoline.

Another factor to consider is engine modifications. Some vehicles may require modifications to the engine or fuel system in order to run on high ethanol blends. It’s important to consult with a mechanic or dealership before making the switch to ensure your vehicle is compatible and safe to use.

Performance and Efficiency

You’ll want to know that getting the most out of high ethanol blends like E15 and E85 means understanding how they affect your vehicle’s performance and fuel efficiency.

While both E15 and E85 contain higher levels of ethanol than regular gasoline, their effects on your vehicle’s performance and fuel economy can vary greatly.

When it comes to fuel economy, E15 typically provides similar or slightly better gas mileage than regular gasoline. However, the same cannot be said for E85, which contains up to 85% ethanol and can result in a significant reduction in fuel economy.

On the other hand, E85 can increase your engine’s power output, making it a popular choice for high-performance vehicles. It’s important to note, however, that not all vehicles are compatible with E85 and using it in a non-flex fuel vehicle can cause damage to your engine.

Ultimately, it’s important to carefully consider your vehicle’s compatibility and your driving needs before choosing a high ethanol blend.


Now that you’ve got a better understanding of E15 and E85, you can make informed decisions about whether to use these ethanol blends in your vehicle.

Keep in mind that E15 is currently approved for use in all vehicles made in 2001 or later, while E85 is only suitable for flex-fuel vehicles.

When deciding which ethanol blend to use, consider factors such as your vehicle’s compatibility, fuel efficiency, and overall cost.

While ethanol is a renewable fuel source that can help reduce our dependence on fossil fuels, it’s important to weigh the pros and cons of using ethanol blends before making a decision.

By taking the time to research and understand the differences between E15 and E85, you can make a more informed choice that aligns with your personal values and priorities.